# Jackson problem 5.4: Magnetic induction in a current-free region

1. May 11, 2017

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution
I think that is taylor series expansion, How that can be expanded right that? even b0, b1 ... is not a differential term.

The solution just use b(z) = Bz(0,z)

2. May 12, 2017

### Twigg

Hint: Try taking the divergence and see what you can do with the $b_{n}$ terms algebraically.